I am looking for recommendations for a good and relatively inexpensive daytime flashing/strobe bike light for my 14 year old son. **He rides to and from school each day and would almost never be riding at night.

I am also looking for a feature that turn the light on when in motion and off when stopped for more then a minute. My son is big of absent minded professor, so he will kill the batteries quick if he had to remember to turn off the light each time.

Anyway recommendations would be greatly appreciated.